New: See more from a follow-up collecting trip.


Rich specimen of
karpatite brilliantly fluorescing under long-wave ultraviolet light. Width 11 cm.


Coronene structure           
Karpatite, C24H12, is a rare hydrocarbon mineral first described from the Transcarpathian mountains of the Ukraine in 1955.

It's pale yellow, very soft (1-1/2), weathers easily, and occurs in thin bladed crystals and powdery masses.

Among chemists this compound is also known as 'coronene' or hexabenzobenzene, and is well known for its fluorescent response to ultraviolet (UV). In fact, it finds use in UV imaging CCDs for the Hubble Space Telescope. MSDS info here.

As a mineral, it provides spectacularly beautiful fluorescent specimens. Response is a brilliant blue-white under long-, mid- and short-wave UV. It also displays strong, if brief, phosphorescence.

In the remote New Idria mining district of San Benito County, California, karpatite can be found very sparingly in thin seams to 1 cm thick in the walls of the Fourth of July Mine.

This page shares a few images from a recent day (and night) trip there to hunt for the elusive karpatite..

Karpatite's daylight appearance (yellow).


Specimen of karpatite broken across seam. LW UV. Width 6 cm.


Rolling farmland approaching the New Idria mining district, San Benito County.

An abandoned prospect in clear sky country.

Gopher snake plainly requesting help to cross the road.

Cinnabar-colored tailings of the abandoned New Idria mercury mines.

Best mineral crystals of the day: water ice.

At last: Entrance to the Fourth of July Mine.

Advance scouting for traces of karpatite, just before nightfall.

Typical weathered surfaces encountered on rock walls of this mine.

Reward for perseverance:
                            (Top) karpatite sample split along seam. LW UV. Width 9 cm.

                                                    (Bottom) close-up view of karpatite seam. LW UV. Field width 2 cm.

See more karpatite from a follow-up collecting trip.


All content Herb Yeates 2005

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